Fluid actuated motor with fluid flow control



Sept. 1, 1964 R. P. STRICK FLUID ACTUATED MOTOR WITH FLUID FLOW CONTROL Filed March 12, 1962 INVENTOR.

Rudolf Poul Str|c k ATTY United States Patent M 3,146,678 FLUID ACTUATED MOTOR WITH FLUID FLOW CONTROL Rudolf Paul Strick, West Roxbury, Mass., assignor to Henry von den Benken, West Roxhury, Mass. Filed Mar. 12, 1962, Ser. No. 179,033 7 Claims. (Cl. 91189) This invention pertains to a fluid actuated motor construction. The motor includes a cylinder, a piston slidably mounted in the cylinder and a cylinder head mounted on one end of the cylinder. The cylinder head has an inlet port, an outlet port and a flow control mechanism so constructed that when fluid under pressure enters the inlet port, the piston is first moved in the cylinder a predetermined amount and then fluid passes through the outlet port. This arrangement enables the piston to perform work followed by the performance of work by an instrumentality connected to the outlet port.

In the specific embodiment of the invention disclosed, the outlet port is connected through a conduit to the inlet port of a second motor constructed similarly to the first mentioned motor and the outlet port of the second motor is connected through a conduit to the inlet port of a third, similarly constructed motor. Thus, the admission of pressurized fluid into the inlet port of the first motor causes the three motors to operate in sequence whereby the first motor is actuated first to perform work, followed by an actuation of the second motor to perform work, and finally by an actuation of the third motor to perform work.

The figure of the drawing shows the three motors in section and a schematic representation of the conduits connected to the motors.

The apparatus comprises a plurality of similar fluid actuated motors, shown by way of example as three motors 10, 12 and 14. Each motor includes a piston 16 movably mounted in a cylinder 18. A conventional O-ring 20 is interposed between each piston and cylinder to provide a seal therebetween. Each piston has a piston rod 22 projecting forwardly thereof through an opening 24 in a front cylinder head 26. Each front cylinder head has a port 27. An O-ring 28 provides for a seal between each piston rod 22 and each cylinder head 26. Each piston 16 has a cylindrical, hollow prong 30 projecting rearwardly thereof, and each prong has a pair of O-rings 32 in its periphery. A cavity 34 is provided in each piston 16 which is in communication with the hole 36 extending through each prong 30. A valve 38 resiliently urged rearwardly by a compression spring 40 serves to yieldably shut off communication between each hole 36 and cavity 34. A duct 42 extends outwardly from each cavity 34 to intersect the rear face 44 of each piston 16.

Each cylinder 18 has a rear cylinder head 46 secured to its rear end, and each cylinder head 46 has an inlet port 48 and an outlet port 50 spaced 180 apart. Each port 48 is in communication with the interior of each cylinder 18 through a passage 52 and a passage 54. A valve 56, yieldably urged rearwardly by a compression spring 58, normally blocks each passage 52. A ferrule 60, threaded into each cylinder head 46, bears against each spring 58. By rotating the corresponding ferrule, the pressure of each spring 58 may be adjusted. A valve 62, yieldably urged forwardly by a compression spring 64, normally blocks each passage 54. Each passage 52 and 54 merges into a passage 66 that intersects the front face 68 of each cylinder head 46 in an area that is in alignment with the area where the corresponding duct 42 intersects its associated piston face 44. Each cylinder head 46 has a cylindrical recess 70 that is in alignment with its corresponding prong 30 and is so dimensioned as to permit the prong 30 to slide therein. A bore 72 3,146,678 Patented Sept. 1, 1964 extends radially from each passage 54 to each recess 70 rearwardly of its associated valve 62, and a bore 74 extends from the rearward end of each recess 70 to the corresponding outlet port 50.

A conduit 76 extends from a source of fluid under pressure (not shown) to the inlet port 48 of the motor 10. A conduit 78 extends from the outlet port 50 of the motor 10 to the inlet port 48 of the motor 12, and a conduit 80 extends from the outlet port 50 of the motor 12 to the inlet port 48 of the motor 14. The outlet port 50 of the motor 14 is blocked by a plug 82. A conduit 84 extending from the source of fluid under pressure has branch lines 86, 88 and 90 respectively extending into the port 27 of the motors 10, 12 and 14.

In the operation of the apparatus, the ferrules 60 are adjusted to provide predetermined pressures in the springs 58 that are greater than the pressures of the springs 40. The pistons 16 are all initially in the rearward position shown by motor 14 in the drawing with each prong 30'within its corresponding recess 70 in a position to block the associated bore 72. Pressurized fluid is admitted into the conduit 76 to enter the cylinder head 46 of the motor 10. This fluid cannot enter the recess 70 because it is blocked by the prong 30 and the sealing rings 32 on the prong, and cannot enter the passage 66 by way of the passage 54 because it is blocked by the valve 62. Therefore, after the fluid pressure is sufliciently high to overcome the force of the spring 58, it moves the valve 56 and enters the passage 66 by way of the passage 52. Most of the fluid exiting from the passage 66 will bear against the piston face 44 to move the piston 16 forwardly while the remainder of the fluid will enter the cavity 34 through the duct 42. The valve 38 blocks the exiting of the fluid from the cavity 34 so that the full fluid pressure is utilized to drive the piston forwardly.

After the piston 16 of the motor 10 has moved forwardly an amount sufficient to move its prong 30 out of blocking relation with respect to its bore 72 (indicated by the position of the motor 12 in the drawing), the pressurized fluid enters the recess 70 of the motor 10. Some of the fluid unseats the valve 38, due to the relative Weakness of the spring 40 with respect to the spring 58 and the tendency of the valve 56 to close when the pressure differential between the port 48 and the passage 52 is less than the pressure of the spring 58, and travels through the cavity 34 and duct 42 to assist in moving the piston 16 forwardly, and the remainder of the fluid travels through the bore 74 and the conduit 78 into the cylinder head 46 of the motor 12. When the piston 16 of the motor 10 has travelled forwardly an amount sufficient to bring its prong 30 out of its associated recess 70, all of the fluid pressure moving forwardly through the recess 70 will bear directly against the piston face 44 of the motor 10.

The fluid pressure will unseat the valve 56 of the motor 12 either after the piston 16 of the motor 10 has completed its forward movement or during the forward movement of the piston depending on the setting of the ferrule 60 of the motor 12. After the unseating of the valve 56 of the motor 12, the operation described for the motor 10 is repeated in the motor 12, and this operation is eventually repeated in the motor 14. When all three motors have been actuated, they assume the position shown for the motor 10 in the drawing, but the above described arrangement enables the motor 10 to be actuated first, followed by an actuation of the motor 12, and finally by an actuation of the motor 14. The plug 82 prevents the exiting of the pressure fluid from the port 50 of the motor 14.

When it is desired to retract the motors, the pressurized fluid coming from the source into the conduit 76 is vented and fluid under pressure is admitted into the conduit 84 to enter the ports 27 of all three motors substantially simultaneously and force all three pistons 16 rearwardly. If the fluid used is relatively incompressible, it tends to be trapped in the recesses 70 when the prongs 30 enter the recesses and also be trapped between the piston faces 44 and the cylinder head faces 68. This is avoided by the valves 38 and 62. When the pistons reach the positions shown for the motor 12 in the drawing, the fluid trapped in the recesses 70 will unseat the valves 38 and travel by way of the cavities 34 and the ducts 42. into the spaces between the pistons 16 and the cylinder heads 46. The fluid in these spaces will unseat the valves 62 and pass into the passages 54 and the conduits '76, 78 and 86 until all three motors reach the position shown for the motor 14 in the drawing.

I claim:

1. A motor system comprising: a cylinder having a first end and a second end; a piston mounted in the cylinder for relative forward movement of the piston with respect to the cylinder from said first end to said second end; a cylinder head at said first end; an inlet port and an outlet port in said cylinder head; fluid flow means in said head providing communication between said ports; a passage connecting said inlet port and said first cylinder end; blocking means connected to the piston for movement therewith positioned to block the fluid flow means when the piston is contiguous to said first end and to unblock said fluid flow means in response to a predetermined amount of said relative forward movement; a fluid pressure actuable work performing instrumentality; and a conduit extending from said outlet port to said work performing instrumentality.

2. The system according to claim 1 further comprising: a normally closed valve in said passage; and means mounting the valve to enable it to open in response to the flow of pressurized fluid in the passage from the inlet port towards the first cylinder end.

3. A motor system comprising: a cylinder; a piston movably mounted in the cylinder; a cylinder head con nected to one end of the cylinder; an inlet port and an outlet port in said cylinder head; a prong on said piston facing said cylinder head; a recess in said cylinder head constructed to snugly and slidably receive said prong; a bore extending from said recess to said outlet port; a first passage extending from said inlet port to said cylinder end; a second passage extending from said inlet port to said recess, the area of intersection of the second passage and the recess being so located as to be blocked by the prong when the piston is contiguous to said cylinder end and to be unblocked from the prong in response to a predetermined amount of movement of the piston away from said cylinder end; a fluid pressure actuable work performing instrumentality; and a conduit extending from said outlet port to said work performing instrumentality.

4. The system according to claim 3 further comprising: a normally closed valve in said first passage; and means mounting the valve to enable it to open in response to the flow of pressurized fluid in said first passage from the inlet port towards said cylinder end.

5. A fluid actuated motor comprising: a cylinder; a piston movably mounted in the cylinder; a cylinder head connected to one end of the cylinder having a face located in the cylinder; an inlet port and an outlet port in said cylinder head; a prong on said piston facing said cylinder head; a recess in said cylinder head constructed to snugly and slidably receive said prong; a bore extending from said recess to said outlet port; a first passage extending from said inlet port to said cylinder head face; a second passage extending from said inlet port to said recess, the area of intersection of the second passage and the recess being so located as to be blocked by the prong when the piston is contiguous to the cylinder head and to be unblocked from the prong in response to a predetermined amount of movement of the piston away from the cylinder head; a fluid pressure actuable work performing instrumentality; and a conduit extending from said outlet port to said work performing instrumentality.

6. A fluid actuated motor according to claim 5 further comprising: valve means in said cylinder head constructed to block said first passage and yieldably openable in response to the flow of pressurized fluid in the passage from the inlet port to the cylinder head face.

7. A fluid actuated motor comprising: a cylinder; a piston movably mounted in the cylinder; a cylinder head connected to the rear end of the cylinder having a face located in the cylidnder; an inlet port and an outlet port in said cylinder head; a prong projecting rearwardly of said piston; a recess in said cylinder head constructed to snugly and slidably receive said prong; a first bore extending from said recess to said outlet port; a first passage extending from said inlet port to said cylinder head face; first valve means in said cylinder head constructed to block said first passage and yieldably openable in response to the flow of pressurized fluid in the first passage from the inlet port to the cylinder head face; a second passage extending from the inlet port to the cylinder head face; second valve means in said cylinder head constructed to block said second passage and yieldably openable in response to the flow of pressurized fluid in the second passage from the cylinder head face to the inlet port; a second bore extending from the second passage to the recess, said second bore intersecting the second passage between the second valve means and the inlet port and intersecting the recess in an area that is so located as to be blocked by the prong when the piston is contiguous to the cylinder head and to be unblocked from the prong in response to a predetermined amount of movement of the piston away from the cylinder head; a third passage extending from the forward end of the prong to the forward face of the piston; third valve means in the piston constructed to block said third passage and yieldably openable in response to the flow of pressurized fluid in the third passage from the prong to the forward face of the piston; a fluid pressure actuable work performing instrumentality; and a conduit extending from said outlet port to said work performing instrumentality.

References Cited in the file of this patent UNITED STATES PATENTS 787,136 Warren Apr. 11, 1905 1,905,065 Scholl Apr. 25, 1933 1,994,974 Wiedmann Mar. 19, 1935 2,719,510 Elder Oct. 4, 1955 2,769,429 Lencioni Nov. 6, 1956 FOREIGN PATENTS 614,469 Great Britain Dec. 16, 1948 

1. A MOTOR SYSTEM COMPRISING: A CYLINDER HAVING A FIRST END AND A SECOND END; A PISTON MOUNTED IN THE CYLINDER FOR RELATIVE FORWARD MOVEMENT OF THE PISTON WITH RESPECT TO THE CYLINDER FROM SAID FIRST END TO SAID SECOND END; A CYLINDER HEAD AT SAID FIRST END; AN INLET PORT AND AN OUTLET PORT IN SAID CYLINDER HEAD; FLUID FLOW MEANS IN SAID HEAD PROVIDING COMMUNICATION BETWEEN SAID PORTS; A PASSAGE CONNECTING SAID INLET PORT AND SAID FIRST CYLINDER END; BLOCKING MEANS CONNECTED TO THE PISTON FOR MOVEMENT THEREWITH POSITIONED TO BLOCK THE FLUID FLOW MEANS WHEN THE PISTON IS CONTIGUOUS TO SAID FIRST END 